Advances in actuation technology for compliant Dextrous manipulation

Moving from antagonistic pneumatic Air Muscle actuation to motor-based actuation requires a distinctly different design of motor component. This design is presented in the context of recent developments on the Shadow Dextrous Hand. Antagonistic systems provide certain advantages, but the constant load on the system produces wear and as it is well known, pneumatics offers its own control and mobility difficulties. In order to replicate this, a smart-motor-unit was developed that simulates the behavior of an antagonistic system without exerting any unnecessary load. This was achieved with a combination of load cells, tensioners, and some nested PID loops. The system is not only able to behave like a pneumatic system, but one can adjust the compliancy in the system.